How to use Generics In Java

Generics in Java are a way to create classes, interfaces, and methods that work with different types of data.

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They allow you to write reusable code that can work with any data type, rather than being limited to a specific type. Here is a simple example of a generic class in Java:

public class GenericExample<T> {
    private T value;
 
    public GenericExample(T value) {
        this.value = value;
    }
 
    public T getValue() {
        return value;
    }
 
    public void setValue(T value) {
        this.value = value;
    }
}

In this example, the class GenericExample is defined with a type parameter T. This means that when an instance of the class is created, the type of value must be specified. For example:

GenericExample<Integer> example1 = new GenericExample<Integer>(5);
Integer value = example1.getValue();

GenericExample<String> example2 = new GenericExample<String>("Hello");
String value2 = example2.getValue();

You can also use generics with interfaces and methods in Java. Here is an example of a generic interface:

interface GenericInterface<T> {
    T getValue();
    void setValue(T value);
}